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arXiv:quant-ph/0001117 · Physical Review A

Motional effects of trapped atomic or ionic qubits

Li You

Published May 30, 2001• 14 citations
arXivHTMLPDF

Abstract

We investigate decoherence effects due to motional degrees of freedom of trapped electronically coded atomic or ionic qubits. For universal single bit rotations implemented with dipole coupling from a near resonant running wave laser, the achievable fidelity is found to depend only on a single parameter characterized by the initial motional state. For two-qubit conditional logic operations inside a high Q optical cavity, we find the popular dark state structure survives even when atomic wave packets are not localized along transverse directions. Our quantitative results provide a useful realistic view for current experimental efforts in quantum logic and computing.

DOI
10.1103/physreva.64.012302

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We investigate decoherence effects due to motional degrees of freedom of trapped electronically coded atomic or ionic qubits. For universal single bit rotations implemented with dipole coupling from a near resonant running wave laser, the achievable fidelity is found to depend only on a single parameter characterized by the initial motional state. For two-qubit conditional logic operations inside a high Q optical cavity, we find the popular dark state structure survives even when atomic wave packets are not localized along transverse directions. Our quantitative results provide a useful realistic view for current experimental efforts in quantum logic and computing.
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